How bad has it gotten for embattled San Diego Mayor Bob Filner ?

Even Hooters -- the restaurant chain sometimes criticized for its scantily clad waitresses -- says he 's no longer welcome .

The chain 's downtown location has joined a campaign by a local radio talk-show host , who 's urging businesses to post signs in their window that declare Filner persona non grata . The signs note that the mayor `` will not be served in this establishment '' and `` We believe women should be treated with respect . ''

In a statement posted on Twitter , the company said restaurant acted on its own .

`` Our Hooters Girls in San Diego have spoken . Not a corporate gig , but we support our girls , '' it read .

San Diego Mayor not welcome : Photos of the Hooters sign

Refusing to resign in the face of mounting allegations that he groped and made lewd comments toward numerous women , Filner is facing an effort to recall him from office . And now a city councilman wants him to answer questions about more than $ 500 in charges on his official city credit card from a downtown hotel .

`` When you see statements like this , it raises the question of is city business being done or not , '' Councilman Kevin Faulconer said Tuesday .

CNN obtained Filner 's municipal credit-card statements from January to May . The taxpayer-paid card included charges ranging from less than $ 30 to about $ 111 at the Westgate Hotel , including one incurred on a Sunday .

The Westgate is across the street from the mayor 's office . Regulars at the bar who did not want to speak on-camera told CNN that Filner was often here , usually with a different woman .

Faulconer , a Republican who sits on the council 's audit committee , raised questions about other charges as well -- $ 3,000 to an online reputation-management firm , $ 128 for a juicer and a $ 30,000 trip to Paris . He said Filner has promised to reimburse the city for that trip , but there has been no proof of a refund .

Secrets that women of San Diego no longer keep about its mayor

The 70-year-old Filner was elected mayor of the eighth-largest American city in 2012 , after 10 terms in Congress . His accusers range from a singer at a campaign fundraiser to his former communications director , who called him unfit for office .

He 's rebuffed calls to resign from all nine City Council members and from his fellow Democrats , including California 's two U.S. senators . He now faces a recall effort that is trying to gather more than 100,000 signatures needed to put his future up to a new vote , though some political observers doubt organizers can succeed .

Filner issued a required response to the notice of a petition drive Tuesday , arguing that voters should weigh his administration 's push for new parks , high-tech jobs , better roads and a 2024 Olympic bid before they decide to whether they want to turn him out of office .

`` Now is not the time to go backwards -- back to the time when middle-class jobs and neighborhood infrastructure were sacrificed to downtown special interests , '' Filner said in a written response to a proposed recall petition . `` We need to continue to move forward ! ''

Did mayor target victims of military sexual assault ?

But Michael Pallamary , the head of the recall effort , said Filner `` obviously believes his policy initiatives excuse his being a sexual predator . ''

`` His reply is unacceptable , '' Pallamary said . `` San Diegans want a mayor that does n't grope and demean women , who does n't abuse his office to satisfy a perverted quest for a sense of power , and who has the ability to lead our great city -- an ability Filner can never , ever reclaim . ''

Filner has brought `` great shame '' on the city , Pallamary said , vowing , `` We will recall him from office . ''

In July , Filner acknowledged that he `` failed to fully respect the women who work for me and with me '' and that he was `` embarrassed '' by his actions . But he also said he will be vindicated by `` a full presentation of the facts '' and he will not resign .

`` We have moved toward the vision of producing thousands of middle-class jobs in our port ; creating a solar-based city to enhance our environment and create jobs ; building an efficient international border to bring billions of dollars into our economy ; keeping our military and hi-tech sectors strong and vibrant , '' Filner said in response to the recall petition notice . He touted new support for the arts , a five-year labor agreement with city workers and work toward bringing the summer Olympics to the city .

Out of rehab , but also locked out of office

The mayor entered a two-week intensive behavior therapy program on July 29 , but his attorney , James Payne , said Filner was able to complete that phase of treatment by Saturday . He 'll continue with outpatient treatment , Payne said -- but he might not be back at work in his office anytime soon . His chief of staff changed the locks , according to numerous reports , including one by CNN affiliate KFMB .

And after weeks of complaints , some observers are questioning whether more should have been said about Filner 's behavior before last year 's election .

`` I think there was a lot of whispering , '' former state Assemblywoman Lori Saldana told CNN . `` It was a lot of things under the surface . A lot of ` boys will be boys . ' ''

Saldana said she brought complaints about Filner to San Diego County 's Democratic Party leader two years ago after hearing accounts of harassing behavior from six women . Nothing happened , she said .

`` It was considered abusive . It was insulting at times . And I think people need to pay attention to those reports , and it did n't happen two years ago , '' said Saldana , also a Democrat .

Filner 's 2012 opponent , City Councilman Carl DeMaio , hinted at the issue during a mayoral debate . Video of the event shows DeMaio telling voters , `` You need a mayor who 's going to insist on zero tolerance of sexual harassment in the workplace '' -- turning to look at Filner while he makes the comment .

DeMaio is now running for Congress and had no comment . But his mayoral campaign featured a television spot in which an Washington airport worker who had a run-in with Filner described his actions as `` scary and hostile . ''

`` I deal with frustrated travelers every day , but I never came across anyone like Bob Filner , '' she said .

Opinion : No room for lecherous mayors

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Hooters , other businesses say Bob Filner is persona non grata

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Filner 's official credit card bills under scrutiny amid complaints

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The San Diego mayor has been accused of sexually harassing numerous women

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Filner answers recall petition drive : `` Now is not the time to go backwards ''